Dust mask



FIG. 1 is a perspective view of a dust mask showing my new design.

FIG. 2 is a left elevation side view of the dust mask shown in FIG. 1 showing my new design, the right side elevation view being a mirror image.

FIG. 3 is a top plan view of the dust mask shown in FIG. 1 showing my new design.

FIG. 4 is a front elevation view of the dust mask shown in FIG. 1 showing my new design.

FIG. 5 is a rear elevation view of the dust mask shown in FIG. 1 showing my new design; and,

FIG. 6 is a bottom plan view of the dust mask shown in FIG. 1 showing my new design.

The broken lines in FIG. 5 illustrate environmental structure of the dust mask, which forms no part of the claimed design. 

CLAIM The ornamental design for a dust mask, as shown and described. 